Camera and a method therein for facilitating installation of the camera

ABSTRACT

There is provided a camera and a method therein for facilitating installation of the camera. The method comprises capturing a video stream of a scene when the camera is installed with a first FOV, which scene comprises an object. A size in the video stream of at least one part of the object is estimated. As long as the estimated size is above a first threshold and below a second threshold, providing a first, edge-filtered, version of the video stream to secure privacy of the object. In response to the estimated size being above the second threshold indicating that the privacy is at risk of being revealed, entering an enhanced secure privacy mode comprising generating an alert to prompt an installer to re-install the camera with a second FOV different from the first FOV, and disabling provision of the first, edge-filtered, version of the video stream.

FIELD OF INVENTION

The present invention relates to a camera and a method therein forfacilitating installation of the camera.

TECHNICAL BACKGROUND

When installing a camera, such as a monitoring camera, to capture imagesof a scene, national privacy regulations may require that privacy of oneor more objects present in the scene should be guaranteed. Privacy istypically achieved by distortion of the captured images such that objectrecognition or object identification is prevented. Thus, by distortingthe captured images facial recognition, identification of registrationnumber of vehicles, etc. is prevented. If the privacy cannot beguaranteed the camera may not be allowed to be installed.

Methods for distorting captured images in order to prevent objectrecognition and objection identification are known. For example, U.S.Ser. No. 10/755,388 B2 describes how to protect personal privacy incaptured image data by controlling privacy masking of an image, wherethe degree of blurring to be applied to a privacy area of the imagedepends on a threshold distance from the image capturing device, and thespatial resolution of content of the scene at this distance in theimage. However, U.S. Ser. No. 10/755,388 B2 is silent about how tofacilitate installation of the camera to guarantee privacy.

US 2014/0362215 A1 relates to correction of a camera installation.However, in this disclosure the aim of the correction of the camerainstallation is to optimize face recognition in the captured images.Average size of faces is measured in different subregions and used asone parameter to trigger a change in camera position, such as moving thecamera further from the scene or zooming in.

Thus, there is room for improvements in order to provide a facilitatedinstallation of a camera fulfilling national privacy regulations.

SUMMARY

In view of the above, mitigating drawbacks with the prior art and toprovide techniques for facilitating installation of a camera, andespecially of a camera able to secure privacy when capturing videostreams would be desirable.

According to a first aspect, the above is achieved by a method,performed by a camera, for facilitating installation thereof. The methodcomprises capturing a video stream of a scene when the camera isinstalled with a first field of view, which scene comprises one or moreobjects. The method further comprises estimating a size in the videostream of at least one part of the one or more objects, and as long asthe estimated size in the video stream of the at least one part of theone or more objects is above a first threshold and below a secondthreshold, providing a first, edge-filtered, version of the video streamto secure privacy of the one or more objects depicted in the videostream. Furthermore, the method comprises, in response to the estimatedsize in the video stream of the at least one part of the one or moreobjects being above the second threshold indicating that privacy of atleast one object is at risk of being revealed, entering an enhancedsecure privacy mode of operation comprising generating an alert toprompt an installer to re-install the camera with a second field of viewdifferent from the first field of view, and disabling provision of thefirst, edge-filtered, version of the video stream.

By providing the first, edge-filtered, version of the video stream aslong as the estimated size in the video stream of the at least one partof the one or more objects is above the first threshold and below thesecond threshold, the privacy of the one or more objects depicted in thevideo stream is secured thanks to the anonymization of the one or moreobjects provided by the first, edge-filtered, version of the videostream.

Further, by disabling the provision of the first, edge-filtered, versionof the video stream when the estimated size in the video stream of theat least one part of the one or more objects being above the secondthreshold indicating that the privacy of at least one object is at riskof being revealed, the privacy of the one or more objects is secured.

By generating the alert to prompt the installer to re-install the camerawhen the estimated size in the video stream of the at least one part ofthe one or more objects being above the second threshold, the installeris made aware of a need to re-install the camera at a second field ofview different from the first field of view in order to secure privacyin the future, i.e., in upcoming captures of video streams. Thus, thesecond field of view should be selected such that it will provideprivacy of one or more objects captured in the video stream.

The term installation when used in this disclosure refers to themounting of the camera at a location, e.g., a physical location, at thescene and/or the configuration of the camera to capture the videostreams of the scene with a certain field of view. Thus, theinstallation may refer to the geographical location at which the camerais mounted and/or to camera settings, such as a certain pan, tilt and/orzoom setting, used for capturing the video streams.

As used herein, the term field of view refers to the part of the scenethat is visible through the camera at a particular position andorientation in space of the camera and at a particular zoom setting ofthe camera. The particular position is given by the installationlocation and the orientation is given by the pan setting and/or tiltsetting of the camera. Thus, it should be understood that the field ofview may depend on one or more different camera parameters. For example,the field of view may depend on the installation location of the camerasuch as height above ground, the zoom setting of the camera the pansetting of the camera and/or the tilt setting of the camera.

The estimated size in the video stream of the at least one part of theone or more objects may be determined as a number of pixels the at leastone part constitute along at least one direction of the video stream.For example, the estimated size of the at least one part may be given asa number of pixels in a vertical (height) direction and/or horizontal(width) direction of an image frame of the video stream. A pixel,sometimes referred to as a picture element, is the smallest singleelement in the image frame. Depending on the spatial resolution of theimage frame, the image frame may comprise 1920×1080 (width×height)pixels, 2560×1440 pixels, 2560×1920 pixels or 3840×2160 pixels, just togive some examples.

The first threshold may be zero pixels in case a first, edge-filtered,version of the video stream should be provided for all estimated sizesbeing below the second threshold. However, if the estimated size in thevideo stream of the at least one part of the one or more objects issmall enough the captured video stream may be provided as it is withoutthe risk of revealing privacy of the one or more objects. What should beconsidered as an estimated size small enough depends on the situation athand, but the first threshold should be set to provide an upperthreshold for when the video stream could be provided as it is withoutrevealing privacy of the one or more objects depicted in the videostream. In such scenario, the first, edge-filtered, version of the videostream is provided when the estimated size in the video stream of the atleast one part of the one or more objects is above the first thresholdbut below the second threshold.

The second threshold should be set to provide an upper threshold forwhen the first, edge-filtered, version of the captured video streamshould be provided. Above this second threshold, the privacy of the oneor more objects is at risk of being revealed if the first,edge-filtered, version of the video stream is provided and therefore theprovision of the first, edge-filtered, version of the video stream isdisabled.

The first and second thresholds may be determined based on cameraparameters and installation location. For example, the thresholds may bedetermined based on the camera's optics such as the type of lens, andthe camera's resolution and field of view. Additionally, oralternatively, the threshold may also be determined based on theedge-filter used to provide an edge-filtered version of the capturedvideo stream and on the size of the edge-filter's kernel. The kernel isa small matrix used in edge detection when performing a convolutionbetween the kernel and the image frame. Further, the first and secondthresholds determined for camera installations in one country may bedifferent from first and second thresholds determined for camerainstallations in another country due to differences in the countries'privacy regulations. The first and second thresholds may be determinedby performing tests or based on first and second thresholds used inprevious camera installations. The first and second thresholds may alsobe determined by means of machine-learning techniques, e.g., by means ofa neural network configured to detect and/or recognize one or moreobjects in a video stream.

It should be understood that the video stream comprises at least oneimage frame of the scene. Thus, the video stream may comprise one imageframe or a plurality of image frames, e.g., a plurality of temporallysubsequent image frame.

The scene may be any three-dimensional physical space whose size andshape is defined by the field of view of a camera recording the scene.

By the term object when used herein is meant any kind of object that mayreveal privacy information about the object itself, about a person beingin possession of the object or about a person being associated with theobject. Thus, the object may be a human person or a part thereof, suchas a face or a body part; a group of people; a vehicle or a partthereof, such as a vehicle license plate, just to give some examples.

An edge-filtered version of the video stream is a version of the videostream wherein edge points have been enhanced and non-edge points havebeen suppressed. The edge points correspond to points in the imageframe(s) of the video stream at which points the image brightnesschanges sharply or, more formally, has discontinuities. Incorrespondence, the non-edge points correspond to pixels in the imageframe(s) at which points the image brightness does not change sharplyor, more formally, does not has discontinuities. In the edge-filteredversion of the video stream, the edge points are enhanced and areusually shown as a set of connected curves that indicate the boundariesof objects, the boundaries of surface markings and/or a set of curvesthat correspond to discontinuities in surface orientation. Since thenon-edge points are suppressed in the edge-filtered version of the videostream, the points within the boundaries enhanced by the edge-points aresuppressed. For example, if contours of a face are enhanced in anedge-filtered version of the video stream, the surface texture withinthe contours of the face would be suppressed, resulting in a degree ofanonymisation of the face. The degree of anonymisation depends on thedegree of enhancement and the degree of suppression in the edge-filteredversion of the video stream. However, it should be understood that thedegree of anonymisation also depends on the spatial resolution of thevideo stream.

In some variants of the method, the enhanced secure privacy mode ofoperation comprises providing a second version of the video stream inwhich the privacy of the one or more objects is further secured.

By providing the second version of the video stream in which the privacyof the one or more objects is further secured, the privacy of the one ormore objects can be guaranteed when it couldn't be guaranteed in thefirst, edge-filtered, version of the video stream which therefore isdisabled. Thereby, the second version of the video stream can beprovided to a user for monitoring or to a storage for storage withoutrevealing any privacy sensitive information.

In some variants of the method, the providing of the second version ofthe video stream comprises producing the second version of the videostream by applying a privacy mask to at least a part of the video streamto secure privacy of the one or more objects depicted in the videostream.

This is a first alternative way of providing the second version of thevideo stream to guarantee the privacy of the one or more objects.

By the term privacy mask when used in this disclosure should beunderstood as a privacy masking feature used to protect personal privacyby concealing parts of an image frame from view with a masked area. Aprivacy mask may be static or dynamic. Static privacy masks typicallystay in place until the operator decides to move or remove them. Dynamicprivacy masks may change over time, and the operator may also definewhen the privacy mask should be applied. For instance, the operatorcould define a dynamic privacy mask such that if a face is detectedwithin the masked area, the face will be masked out, but otherwise nomask will be applied to the area.

Privacy masks are often applied to the image as an overlay. The privacymask may have a polygonal shape, but other shapes are also possible,which more closely follow the shape of the area to occlude. Some privacymasks take the form of an opaque area (e.g., a uniformly black or bluearea), while other privacy masks take the form of blurring, where imagedata is “smeared” out over the privacy mask area, or pixilation.Pixilation is a process where a single pixel value (often an averagevalue of several or all the pixels within a coding unit) replaces allthe pixels in a coding unit. Pixilation may be achieved by downscalingthe image frame a factor between e.g., 8 and 64, and thereafterupscaling the image frame using a trivial scaling algorithm, such asnearest neighbour algorithm. In general, though, blurring for privacymasking is considered more desirable than pixilation as it allows forsmoother edges and is therefore nicer looking. However, blurring is moredifficult to a achieve and requires more computational resources toimplement than what is currently economically viable in a hardwareblock.

In a video stream, the privacy mask is applied to each image frame ofthe video stream to conceal privacy of the one or more objects depictedin the video stream. For example, the privacy mask may be applied to aface or a body part of a human person and thereby conceal those partsfrom view and identification. The privacy mask may be applied to the atleast one part of the video stream, by determining an area covering theone or more objects depicted in the video stream and by presenting thearea using a solid colour, blurring or pixilation as mentioned above.The area may for example be determined as the outlines of the one ormore objects. However, the area may have another shape, e.g., circular,rectangular, oval, suitable for covering the at least one part of thevideo stream.

In some variants of the method, the providing of the first,edge-filtered, version of the video stream comprises producing thefirst, edge-filtered, version of the video stream by applying an edgefilter to the video stream to enhance edge points in the video streamand to suppress non-edge points in the video stream, wherein pixelvalues of the video stream are represented using a first number ofquantization levels.

As mentioned above, by producing the first, edge-filtered, version ofthe video stream, the privacy of the one or more objects depicted in thevideo stream is secured thanks to the anonymization of the one or moreobjects provided by the first, edge-filtered, version of the videostream.

The edge filter is a filter that enhances edge points and suppressesnon-edge points. Thus, by applying the edge filter to the video streamedge points will be enhanced while non-edge points will be suppressed.For example, the edge filter, sometimes also referred to as an edgedetection filter, may be a Sobel filter, a Canny filter, a Difference ofGaussian (DoG) filter, a Laplacian filter, a Prewitt filter, or a Scharrfilter, just to give some examples. In order to fit the use case, theoutput of the edge filter, i.e., the edge-filtered version of the videostream, may be modified using one or more operations, such as anabsolute-value operation to not differentiate between positive andnegative gradients, a gain operator to adjust strength, an offsetoperator to make edge points black and non-edge points white, and/or anoise reduction operator to remove unnecessary sparse black edge pixelsnot part of real edges or other structures in the image.

As mentioned above, pixels in the video stream will be represented usinga first number of quantization levels. For example, the pixels may berepresented using 8 bits corresponding to 256 quantization levels. Thus,each pixel may take a value between 0 and 255 to represent one of the256 possible colours. After applying an edge filter to a video stream,the resulting edge-filtered version of the video stream is usuallycomposed of pixels having a value on a greyscale meaning that they areonly representing an amount of light, that is, each pixel representsonly intensity information. In case of an 8 bits representation, eachpixel of the edge-filtered version of the video stream will be able torepresent a level of intensity between 0 and 255 using a greyscale.Thus, if 0 is represented by white and 255 by black, there is 254 shadesof grey in between.

In some variants of the method, the providing of the second version ofthe video stream comprises producing the second version of the videostream as a second, edge-filtered, version of the video stream by,before applying the edge filter to the video stream, reducing thespatial resolution of the video stream in order to reduce the size inthe video stream of the at least one part of the one or more objects tobe below the second threshold.

This is a second alternative way of providing the second version of thevideo stream to guarantee the privacy of the one or more objects. Forsome uses cases, this may be an effective way to guarantee the privacyof the one or more objects.

The term spatial resolution when used herein refers to the number ofpixels utilized in construction of the video stream, e.g., inconstruction of one or more image frames of the video stream. Byreducing the spatial resolution of the video stream, the number ofpixels composing the one or more image frames of the video stream isreduced. This is sometimes referred to as downscaling or downsampling.In correspondence, by increasing the spatial resolution of the videostream, i.e., by upscaling/upsampling the video stream, the number ofpixels composing the one or more image frames of the video stream isincreased. It should be understood that the size of each pixel remainsthe same resulting in a reduced image size when the spatial resolutionis reduced and in an increased image size when the spatial resolution isincreased. Thereby, the video streams, e.g., the original captured videostream, the first version of the video stream and the second version ofthe video stream will all have the same pixel size if provided to a userirrespective of the level of privacy. However, it should be understoodthat after downscaling of a video stream, upscaling of the video streammay be performed to keep the video stream with the same number of pixelsbut with less sensitive information since image details are lost duringdownscaling.

By reducing the spatial resolution of the video stream so that the sizein the video stream of the at least one part of the one or more objectsto be below the second threshold it is guaranteed that privacy of theone or more objects is obtained in the second, edge-filtered, version ofthe video stream.

In some variants of the method, the providing of the second version ofthe video stream comprises producing the second version of the videostream as a second, edge-filtered, version of the video stream by,before applying the first edge filter to the video stream, reducing thenumber of quantization levels used to represent pixel values of thevideo stream from the first number of quantization levels to a secondnumber of quantization levels.

This is a third alternative way of providing the second version of thevideo stream to guarantee the privacy of the one or more objects. Itshould be understood that pixel values in the second, edge-filtered,version of the video stream will be represented using the second numberof quantization levels.

By reducing the number of quantization levels in the video stream fromthe first number of quantization levels to a second, lower, number ofquantization levels, the granular distortion in the second,edge-filtered, version of the video stream will be increased due to thelarger number of intensities to be represented by each quantizationlevel in the second number of quantization levels as compared to thenumber of intensities to be represented by each quantization level inthe first number of quantization levels. Thanks to a larger granulardistortion, the privacy of the one or more objects depicted in thesecond, edge-filtered, version of the video stream is secured.

For example, if the first number of quantization levels was 256 asmentioned above using the 8 bits representation, the number of secondquantization levels may be 4 (using a 2 bits representation). In suchcase, the 256 quantization levels of the first number of quantizationlevels each representing one intensity, are grouped into four groups of64 quantization levels. The first group may be combined into a firstquantization level (e.g., 0) of the second number of the quantizationlevels. Thus, this first quantization level (e.g., 0) of the secondnumber of the quantization levels will represent each one of the 64different intensities represented by the quantization levels 0-63 of thefirst number of quantization levels. Therefore, in the second,edge-filtered, version of the video stream it will not be possible tosee any differences between the 64 different intensities represented bythe quantization levels 0-63 of the first number of quantization levelsin the first, edge-filtered, version of the video stream. Incorrespondence, the second group may be combined into a secondquantization level (e.g., 1) of the second number of the quantizationlevels, and this second quantization level (e.g., 1) will represent eachone of the 64 different intensities represented by the quantizationlevels 64-127 of the first number of quantization levels. Therefore, inthe second, edge-filtered, version of the video stream it will not bepossible to see any differences between the 64 different intensitiesrepresented by the quantization levels 64-127 of the first number ofquantization levels in the first, edge-filtered, version of the videostream. The same is true for the third and four groups.

In some variants of the method, providing the second version of thevideo stream comprises producing the second version of the video streamas a second, edge-filtered, version of the video stream by, reducing thespatial resolution of the first, edge-filtered, version of the videostream to obtain the second, edge-filtered, version of the video streamwherein the size of the at least one part of the one or more objects isbelow the second threshold.

This is a fourth alternative way of providing the second version of thevideo stream to guarantee the privacy of the one or more objects.

By reducing the spatial resolution of the first, edge-filtered, versionof the video stream to obtain the second, edge-filtered, version of thevideo stream wherein the size of the at least one part of the one ormore objects is below the second threshold, the privacy of the one ormore objects is secured.

In some variants of the method, the providing of the second version ofthe video stream comprises producing the second version of the videostream as a second, edge-filtered, version of the video stream byrepresenting edge points having an edge strength below an edge strengththreshold in the first, edge-filtered, version of the video stream asnon-edge points in the second, edge-filtered, version of the videostream.

This is a fifth alternative way of providing the second version of thevideo stream to guarantee the privacy of the one or more objects. Byrepresenting edge points having an edge strength below the edge strengththreshold in the first, edge-filtered, version of the video stream asnon-edge points in the second, edge-filtered, version of the videostream, the contours of the one or more objects are further enhancedwhile the surface texture within the contours of the one or more objectsare further suppressed. That results in a higher degree of anonymisationof the one or more objects and thereby secures the privacy of the one ormore objects. The expression “edge strength” refers to a measure of theedge and how sharply the image brightness changes at the edge.

In some variants of the method, providing the first, edge-filtered,version of the video stream comprises transmitting the first,edge-filtered, version of the video stream to a receiver; and disablingprovision of the first, edge-filtered, version of the video streamcomprises disabling transmission of the first, edge-filtered, version ofthe video stream to the receiver.

The receiver may be any device operatively connected, via wire orwirelessly, to the camera either directly or indirectly via a network.For example, the receiver may be a storage, a user terminal, a server ora cloud device.

In some variants of the method, disabling provision of the first,edge-filtered, version of the video stream comprises disabling thecamera from capturing the video stream. By disabling the camera fromcapturing the video stream means that the capturing of the video streamis terminated. Thereby, there is no captured video stream that may riskrevealing the privacy of the one or more objects if provided.

In some variants of the method, disabling provision of the first,edge-filtered, version of the video stream comprises disabling an imagesensor of the camera to convey image information used to make thecaptured video stream.

By disabling the image sensor to convey image frames used to make thecaptured video stream, there is no image information to process and thusno captured video stream that may reveal privacy if provided.

In some variants of the method, the method further comprises when theestimated size in the video stream of the at least one part of the oneor more objects is below the first threshold, providing the capturedvideo stream.

Thus, when the size in the video stream of the at least one part of theone or more objects is below the first threshold, it is concluded thatthe captured video stream would not reveal privacy if it is provided asit is. Therefore, the captured video stream is provided when the size inthe video stream of the at least one part of the one or more objects isbelow the first threshold.

According to a second aspect, the above is achieved by a camera forfacilitating installation thereof. The camera comprises an imagecapturing module configured to capture a video stream of a scene whenthe camera is installed with a first field of view, which scenecomprises one or more objects; a size estimating component configured toestimate a size in the video stream of at least one part of the one ormore objects; a providing component configured to, as long as theestimated size in the video stream of the at least one part of the oneor more objects is above a first threshold and below a second threshold,provide a first, edge-filtered, version of the video stream to secureprivacy of the one or more objects depicted in the video stream. Inresponse to the estimated size in the video stream of the at least onepart of the one or more objects being above the second thresholdindicating that privacy of at least one object is at risk of beingrevealed, the camera is configured to enter an enhanced secure privacymode of operation wherein an alert generating component is configured togenerate an alert to prompt an installer to re-install the camera with asecond field of view different from the first field of view, and whereinthe providing component is configured to disable provision of the first,edge-filtered, version of the video stream.

According to a third aspect, the above is achieved by a non-transitorycomputer-readable medium having stored thereon computer codeinstructions adapted to carry out the method of the first aspect whenexecuted by a device having processing capability.

The second and third aspects may generally have the same features andadvantages as the first aspect. It is further noted that the conceptsherein to all possible combinations of features disclosed herein unlessexplicitly stated otherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as additional objects, features and advantages, willbe better understood through the following illustrative and non-limitingdetailed description of embodiments, with reference to the appendeddrawings, where the same reference numerals will be used for similarelements, wherein:

FIG. 1 schematically an exemplary environment in which variousembodiments can be implemented.

FIG. 2 schematically illustrates a camera according to embodiments.

FIG. 3 is a flowchart of a method for facilitating installation of acamera according to embodiments.

FIG. 4 schematically illustrates an image processing pipeline accordingto embodiments.

FIG. 5 schematically illustrates an image frame of a captured videostream depicting four objects.

FIG. 6 schematically illustrates a privacy masked image frame of acaptured video stream securing privacy of four objects.

FIG. 7 schematically illustrates an edge-filtered image frame of afirst, edge-filtered, version of a captured video stream depicting thefour objects.

FIG. 8 schematically illustrates an example of an edge-filtered imageframe of a second, edge-filtered, version of a captured video stream.

FIG. 9 schematically illustrates an example of an edge-filtered imageframe of another second, edge-filtered, version of a captured videostream.

FIG. 10 schematically illustrates an example of an edge-filtered imageframe of an edge-filtered version of a captured video stream.

FIG. 11 schematically illustrates an example of an edge-filtered imageframe 1100 of a second, edge-filtered, version of a captured videostream, wherein the number of quantization levels is reduced.

FIG. 12 schematically illustrates an example of an edge-filtered imageframe 1200 of a second, edge-filtered, version of a captured videostream.

DETAILED DESCRIPTION

The present teachings will be described more fully hereinafter withreference to the accompanying drawings, in which embodiments are shown.

FIG. 1 shows a schematic diagram of an exemplary environment 100 inwhich various embodiments can be implemented. As can be seen in FIG. 1,a scene 102 with an object 104, e.g., a person walking towards abuilding 106 is captured by a camera 108 mounted at a pole 109. Itshould be noted that the depiction of the scene 102 is merely asimplistic view for illustrative purposes. A scene 102 can be described,in a more general sense as any three-dimensional physical space whosesize and shape is defined by the field of view of a camera recording thescene. Further, it should be understood that the camera 108 may bemounted at other suitable places, such as on a building, in a ceiling,on a wall or a fence, and thus that the mounting at the pole 109 is justgiven as an example.

The camera 108 may be a monitoring camera, sometimes also referred to assurveillance camera. Further, the camera may be a fixed camera, e.g., astationary camera, or a movable camera, e.g., a pan, tilt and zoom (PTZ)camera or a body worn camera (BWC). The camera 108 may be a visiblelight camera, an infrared (IR) sensitive camera or a thermal(long-wavelength infrared (LWIR)) camera.

As illustrated in FIG. 1, the camera 108 is configured to transmit thevideo streams wirelessly over a radio link 110 to a wired network 112,and eventually to a client 114 and/or a server 116, which may beconnected to the network 112. It should be understood that there aremany combinations of wireless and wired transmission models that can beused, and that FIG. 1 only illustrates one example.

The client 114 may have a display where an operator can view imagesand/or video streams from the camera. Typically, the client 114 is alsoconnected to the server 116, where the images and/or video streams canbe stored and/or processed further. Often, the client 114 is also usedto control the camera 108, for example, by the operator issuing controlcommands at the client 114. For example, an operator may instruct thecamera to zoom out on a particular detail of the scene 102. This may bethe case when a size in the video stream of a part of the one or moreobjects 104 are estimated to be above a second threshold when capturingvideo streams using a first field of view, e.g., a first zoom setting,and an alert is generated to an installer who can instruct the camera tozoom out on the part of the one or more objects to reduce the size inthe video stream of the part to be below the second threshold whencapturing video streams using a second field of view, e.g., a secondzoom setting, that is different from the first field of view. Therebyprivacy of the one or more objects can be secured. However, there arealso situations in which an operator does not control the camera, butthe camera 108 is stationary and merely provides the video stream forthe operator to view on the client 120. In such scenario, the installermay need to re-install the camera 108 at another physical location inorder to obtain the second field of view in which the size in the videostream of the part is below the second threshold when capturing videostreams using this second field of view. Thus, a re-installation of thecamera 108 at a different physical location may also obtain thesought-after secured privacy of the one or more objects. The differentphysical location may be a location at a larger distance from the one ormore objects as compared to the distance to the one or more objects wheninstalled with the first field of view.

FIG. 2 schematically illustrates embodiments of the camera 108.

The camera 108 comprises a lens 202 that captures the scene 102 andprojects it onto an image sensor 204. Together, the lens 202 and imagesensor 204 may form an image capturing module 206. The image sensor 204captures image frames forming video streams. The camera comprisesfurther an image processing pipeline (IPP) 208, an encoder 210 and aninput/output interface 212.

The image processing pipeline 208 is configured to perform a range ofvarious operations on image frames received from the image sensor 204.Such operations may include filtering, demosaicing, colour correction,noise filtering for eliminating spatial and/or temporal noise,distortion correction for eliminating effects of e.g., barreldistortion, global and/or local tone mapping, e.g., enabling imaging ofscenes containing a wide range of intensities, transformation, e.g.,rotation, flat-field correction, e.g., for removal of the effects ofvignetting, application of overlays, e.g., privacy masks, explanatorytext, etc. However, it should be noted that some of these operations,e.g., transformation operations, such as correction of barreldistortion, rotation, etc., may be performed by one or more modules,components or circuits arranged outside the image processing pipeline208, for example in one or more units between the image processingpipeline 208 and the encoder 210.

Following the image processing pipeline 208, the image frames areforwarded to the encoder 210, in which the image frames are encodedaccording to an encoding protocol and forwarded to a receiver, e.g., theclient 114 and/or the server 116, over the network 112 using theinput/output interface 212. It should be noted that the camera 108illustrated in FIG. 2 also includes numerous other components, such asprocessors, memories, etc., which are common in conventional camerasystems and whose purpose and operations are well known to those havingordinary skill in the art. Such components have been omitted from theillustration and description of FIG. 2 for clarity reasons.

The camera 108 may also comprise a data storage 214 for storing datarelating to the capturing of the video stream and data relating to themethod for facilitating installation of the camera 108. Thus, the datastorage may store the captured video stream, first and second versionsof the video stream, first and second thresholds, first and second fieldof views, estimated size in the video stream of at least one part of oneor more objects, just to give some examples. The data storage may be anon-volatile memory, such as an SD card.

There are a number of conventional video encoding formats. Some commonvideo encoding formats that work with the various embodiments include:JPEG, Motion JPEG (MJPEG), High Efficiency Video Coding (HEVC), alsoknown as H.265 and MPEG-H Part 2; Advanced Video Coding (AVC), alsoknown as H.264 and MPEG-4 Part 10; Versatile Video Coding (VVC), alsoknown as H.266, MPEG-I Part 3 and Future Video Coding (FVC); VP9, VP10and AOMedia Video 1 (AV1), just to give some examples.

As mentioned, the input and output interface 212 is configured to act asa communication interface between the camera 108, the network 112 andone or more receiving devices such as the client 114 and the server 116.Thus, the camera 108 may receive instructions from the client 114 andmay transmit video streams to the client and/or the server 116 via theinput and output interface 212.

The image processing pipeline 208, the encoder 210 and the input/outputinterface 212 may form an image processing and encoding module 214,which is connected to the image capturing module 206. The imagecapturing module 206 and the image processing and encoding module 214may be arranged as two separate units arranged at a distance from eachother and in communication with each other. In such scenario the camera108 may also be referred to as a camera system. Alternatively, the imagecapturing module 206 and the image processing and encoding module 214may be arranged as a single unit comprised in the camera 108. Further,the image capturing module 206 may be movable, e.g., in pan and/or tiltdirections, while the image processing and encoding module 214 may bestationary.

A method for facilitating installation of the camera 108 will now bedescribed with reference to the flowchart of FIG. 3 and with referenceto FIGS. 2 and 4. FIG. 4 schematically illustrates the image processingpipeline 208 according to embodiments. As illustrated, embodiments ofthe image processing pipeline 208 comprises a size estimating component402, a providing component 404 and an alert generating component 406.However, it should be understood that one or more of the size estimatingcomponent 402, the providing component 404 and the alert generatingcomponent 406 may be arranged in the camera 108 in another way. Forexample, the camera 108 may comprise one or more of the size estimatingcomponent 402, the providing component 404 and the alert generatingcomponent 406 as separate units communicatively connected to each otherand to other parts of the camera 108 such as the image processingpipeline 208, the encoder 210, the input and output interface 212, andthe data storage 214.

Further, it should be understood that the method illustrated in FIG. 3may be performed by different parts of the camera 108, that some of thesteps may be optional and that steps may be taken in another suitableorder. Furthermore, in this disclosure one or more steps are describedas being performed on an image frame of the captured video stream. Thismay be understood as one or more steps may be performed on a temporalpart of the video stream.

In step S302, a video stream of the scene 102 is captured when thecamera 108 is installed with a first field of view. This step isperformed by the image capturing module 206, e.g., by the lens 202 andthe image sensor 204.

As previously mentioned, the scene 102 comprises one or more objects104.

As also previously mentioned, the term field of view refers to the partof the scene that is visible through the camera 108 at a particularposition and orientation in space of the camera 108 and at a particularzoom setting of the camera 108. The particular position is given by theinstallation location and the orientation is given by the pan settingand/or tilt setting of the camera. Thus, it should be understood thatthe first field of view may depend on one or more different cameraparameters. For example, the first field of view may depend on theinstallation location of the camera 108 such as height above ground, thezoom setting of the camera 108, the pan setting of the camera 108 and/orthe tilt setting of the camera.

Further, and as previously mentioned, the one or more objects 104 may beany kind of object that may reveal privacy information about the objectitself, about a human person being in possession of the object or abouta human person being associated with the object. Thus, the object may bea human person or a part thereof, such as a face or a body part; a groupof people; a vehicle or a part thereof, such as a vehicle license plate,just to give some examples.

FIG. 5 schematically illustrates an image frame 500 of a captured videostream depicting four objects 104, e.g., four individuals 104 a, 104 b,104 c, 104 d, walking on a pavement.

In step S304, a size in the video stream of at least one part of the oneor more objects 104 is estimated. This step may be performed by the sizeestimating component 402. The size in the video stream of the at leastone part of the one or more objects may be estimated as a number ofpixels the at least one part constitutes along at least one direction ofthe video stream. For example, the estimated size of the at least onepart may be given as a number of pixels in a vertical (height) directionand/or horizontal (width) direction of an image frame of the videostream. Thus, the estimated size may be a length, a height, a width or adistance between two points given as a number of pixels. For example,the estimated size may be the number of pixels between an individual'seyes or the number of pixels between the left side of the individual'sface and the right side of the face. However, the estimated size mayalso be the number of pixels the at least one part, e.g., an area,comprises in the image frame. In embodiments, wherein the estimated sizeis estimated as a size in the video stream of a face of an individual,the estimating component 402 may comprise or may be connected to a facedetector (402 a) configured to detect faces in video streams. However,the estimating component 402 may in addition or alternatively, compriseor may be connected to one or more other object detectors (402 b)configured to detect other objects or parts thereof, such as vehiclesand license plates. In FIG. 5 bounding boxes 104 a′, 104 b′, 104 c′, 104d′ schematically illustrate the individuals' 104 a-104 d faces asdetected by for example the face detector 402 a. The size of a vehiclein the captured video may e.g., be detected by the object detector 402 bestimating the distance between the vehicle's headlamps or estimatingthe size of the vehicle's licenses plate in the captured video stream.

In step S306 and as long as the estimated size in the video stream ofthe at least one part of the one or more objects 104 is above a firstthreshold and below a second threshold, a first, edge-filtered, versionof the video stream is provided to secure privacy of the one or moreobjects 104 depicted in the video stream. This step is performed by theproviding component 404.

In some embodiments, the providing of the first, edge-filtered, versionof the video stream comprises producing the first, edge-filtered,version of the video stream by applying an edge filter to the videostream to enhance edge points in the video stream and to suppressnon-edge points in the video stream. The pixel values of the videostream and the pixel values of the first, edge-filtered, version of thevideo stream are represented using a first number of quantizationlevels.

The providing of the first, edge-filtered, version of the video streammay comprise transmitting the first, edge-filtered, version of the videostream to a receiver. As previously mentioned, the receiver may be anydevice operatively connected, via wire or wirelessly, to the camera 108or being comprised within the camera 108. Thus, it should be understoodthat the first, edge-filtered, version of the video stream may betransmitted to the client 114, the server 116 and/or to the data storage214.

FIG. 7 schematically illustrates an edge-filtered image frame 700 of thefirst, edge-filtered, version of the captured video stream depicting thefour objects 104, e.g., the four individuals 104 a, 104 b, 104 c, 104 d.The edge-filtered image frame 700 is obtained by applying a Sobel filterto the image frame 500 and has the highest possible spatial resolution.By the highest possible spatial resolution is meant that the spatialresolution of the edge-filtered image frame is the same as thecorresponding image frame of the captured video stream. In other words,the spatial resolution of the edge-filtered image frame 700 is the sameas the spatial resolution of the image frame 500. As can be seen in FIG.7, the privacy of the individuals is revealed as they are coming closerto the camera and thus, when the size of for example their faces in theimage frame 700 increases. Therefore, before the privacy is revealed,e.g., already when the privacy of the one or more objects is at risk ofbeing revealed, the providing of the first, edge-filtered, version ofthe captured video stream should be disabled.

Therefore, in step S308 and in response to the estimated size in thevideo stream of the at least one part of the one or more objects 104being above the second threshold indicating that privacy of at least oneobject is at risk of being revealed, the camera 108 enters an enhancedsecure privacy mode of operation.

When in the enhanced secure privacy mode of operation, in step S310 analert is generated to prompt an installer to re-install the camera 108with a second field of view different from the first field of view, andin step S312 provision of the first, edge-filtered, version of the videostream is disabled. The provision of the first, edge-filtered, versionof the video stream may be disabled for a predetermined period of time,e.g., for a period of time corresponding to one or more days, or to aperiod of time expected to be needed for the re-installation of thecamera 108.

It should be understood that the re-installation of the camera 108 inorder to obtain the second, different, field of view may comprisechanging the camera settings from a first pan level to a second,different, pan level, and/or from a first tilt setting to a second,different, tilt setting and/or from a first zoom setting to a second,different, zoom setting. The second zoom setting is preferably a zoomout setting as compared to the first zoom setting. Alternatively, oradditionally, the re-installation may comprise that the camera 108 ismoved from a first physical location to a second, different, physicallocation, i.e., from a mounting on a pole on the ground to a mounting uphigh on a high building.

After the re-installation of the camera 108 with the second field ofview, the method steps may be repeated from step S302 now with thesecond field of view being a new first field of view, i.e., the firstfield of view mentioned in the steps S302-S312.

Step S310 may be performed by the alert generating component 406, andstep S312 may be performed by the providing component 404.

In some embodiments, the disabling of the provision of the first,edge-filtered, version of the video stream comprises disablingtransmission of the first, edge-filtered, version of the video stream tothe receiver. This means that in some embodiments, the camera 108 stopsrecording the first, edge-filtered, version of the video stream. Forexample, the first, edge-filtered, version of the video stream is notstored in the data storage 214.

Alternatively, in some embodiments, the disabling of the provision ofthe first, edge-filtered, version of the video stream comprisesdisabling the camera from capturing the video stream. This may be thecase, when no second version of the video stream is needed or desiredand thus the camera 108 is inactivated when the first, edge-filtered,version of the video stream cannot guarantee privacy of the one or moreobjects. In such case, the image capturing module 206, e.g., the lens202 and/or the image sensor 204, may be disabled from capturing thevideo stream.

In some embodiments, the disabling of the provision of the first,edge-filtered, version of the video stream comprises disabling an imagesensor of the camera to convey image information used to make thecaptured video stream. Thus, in some cases the camera 108 is disabled bydisabling the image sensor 204 from conveying image frames used to makethe captured video stream. For example, the image sensor 204 may bedisabled from conveying image frames to the image processing andencoding module 214 of the camera 108.

In an optional step S314, the enhanced secure privacy mode of operationfurther comprises, providing a second version of the video stream inwhich the privacy of the one or more objects 104 is further secured.This step may be performed during the predetermined period of timementioned in step S312 above, and during which period of time theprovision of the first, edge-filtered, version of the video stream isdisabled awaiting re-installation of the camera 108. As will bedescribed below, the provisioning of the second version of the videostream may be accomplished in different ways.

In a first alternative way, the providing of the second version of thevideo stream comprises producing the second version of the video streamby applying a privacy mask to at least a part of the video stream tosecure privacy of the one or more objects 104 depicted in the videostream. The privacy mask may be a colour mask or a mosaic (pixel) mask.For example, the privacy mask masks the identities of objects in liveand recorded video streams by comparing a live camera view with a setbackground scene and applying dynamic masking to areas ofchange—essentially moving objects. Further, it may be possible to setthe level of masking required. The colour masking may provide thegreatest privacy protection of the two while enabling viewing ofmovements. Mosaic masking shows moving objects in a low resolution andit may be easier to distinguish forms by seeing an object's differentcolours as compared to the colour mask applying a single masking colourto the entire object.

FIG. 6 schematically illustrates a privacy masked image frame 600 of thecaptured video stream securing privacy of the four objects 104, e.g.,the four individuals 104 a, 104 b, 104 c, 104 d.

In a second alternative way, the providing of the second version of thevideo stream comprises producing the second version of the video streamas a second, edge-filtered, version of the video stream by, beforeapplying the edge filter to the video stream, reducing the spatialresolution of the video stream to reduce the size in the video stream ofthe at least one part of the one or more objects to be below the secondthreshold. As previously mentioned, by reducing the spatial resolutionof the video stream, before applying the edge filter, such that the sizein the video stream of the at least one part of the one or more objectsis below the second threshold, the privacy of the one or more objects issecured in the second, edge-filtered, version of the video stream.

FIG. 8 schematically illustrates an example of an edge-filtered imageframe 800 of the second, edge-filtered, version of the captured videostream. The spatial resolution of the edge-filtered image frame 800 ishalf the spatial resolution of the edge-filtered image frame 700. As canbe seen by comparing the edge-filtered image frames 700, 800, the sizeof the edge-filtered image frame 800 is reduced as compared to the imagesize of the edge-filtered image frame 700. However, as seen in theedge-filtered image frame 800 the privacy of the four individuals is notsecured. In order to secure privacy, the spatial resolution should bereduced even more before applying the edge-filter in order to reduce thesize in the video stream of the at least one part of the one or moreobjects to be below the second threshold. FIG. 9 schematicallyillustrates an example of an edge-filtered image frame 900 of anothersecond, edge-filtered, version of the captured video stream. The spatialresolution of the edge-filtered image frame 900 is a fourth of thespatial resolution of the edge-filtered image frame 700. As isillustrated in FIG. 9, the privacy of the four individuals is secured inthe edge-filtered image frame 900.

In a third alternative way, the providing of the second version of thevideo stream comprises producing the second version of the video streamas a second, edge-filtered, version of the video stream by, beforeapplying the edge filter to the video stream, reducing the number ofquantization levels used to represent pixel values of the video streamfrom the first number of quantization levels to a second number ofquantization levels.

It should be understood that pixel values of the second, edge-filtered,version of the video stream may be represented using the second numberof quantization levels.

However, it should also be understood that the number of possiblequantization levels may be increased again to correspond to the firstnumber of quantization levels and that in such scenario only a number ofthe quantization levels corresponding to the second number ofquantization levels is used to represent the pixel values of the second,edge-filtered, version of the video stream. For example, if the firstnumber of quantization levels of the video stream corresponds to 256 (8bits), and the second number of quantization levels is 16 (4 bits), thesecond, edge-filtered, version of the video stream may be a 4 bits videostream wherein the 16 quantization levels are used to represent pixelvalues or its number of quantization levels may be increased to 256 (8bits) but only 16 quantization levels out of the 256 quantization levelsare used to represent pixel values.

As previously set forth, by reducing the number of quantization levelsused in the video stream from the first number of quantization levels toa second, lower, number of quantization levels, the granular distortionin the second, edge-filtered, version of the video stream will beincreased due to the larger number of intensities to be represented byeach quantization level in the second number of quantization levels ascompared to the number of intensities to be represented by eachquantization level in the first number of quantization levels. Thanks toa larger granular distortion, the privacy of the one or more objectsdepicted in the second, edge-filtered, version of the video stream issecured.

FIG. 11 schematically illustrates an example of an edge-filtered imageframe 1100 of a second, edge-filtered, version of the captured videostream, wherein the number of quantization levels has been reduced inorder to secure privacy. In the exemplifying figure, the number ofquantization levels in the edge-filtered image frame 1100 is 8 (3 bits)as compared to the 256 quantization levels (8 bits) in the edge-filteredimage frame 700.

In a fourth alternative way, the providing of the second version of thevideo stream comprises producing the second version of the video streamas a second, edge-filtered, version of the video stream by, reducing thespatial resolution of the first, edge-filtered, version of the videostream to obtain the second, edge-filtered, version of the video streamwherein the size of the at least one part of the one or more objects isbelow the second threshold. As previously mentioned, by reducing thespatial resolution of the first, edge-filtered, version of the videostream the number of pixels composing the one or more image frames ofthe first, edge-filtered, version of the video stream is reduced.Further, by reducing the spatial resolution of the first, edge-filtered,version of the video stream such that the size in the second,edge-filtered, version of the video stream of the at least one part ofthe one or more objects is below the second threshold, the privacy ofthe one or more objects is secured in the second, edge-filtered, versionof the video stream when the privacy could not be guaranteed in thefirst, edge-filtered, version of the video stream.

In order to secure privacy for objects depicted in different areas ofthe captured video stream, a first image resolution of a first area ofthe edge-filtered image frame depicting a first object may be differentfrom a second image resolution of a second area of the edge-filteredimage frame depicting a second object. The first image resolution of thefirst area relates to an amount of image details in the first area, andin correspondence, the second image resolution of the second arearelates to an amount of image details in the second area. The first andsecond image resolutions may be obtained by downscaling the first andsecond areas differently and then upscaling them to comprise theiroriginal number of pixels. As previously mentioned, downscaling reducesthe number of pixels causing image details to be lost, and upscalingincreases the number of pixels but cannot recover lost image details.Thus, by downscaling the first and second areas differently differentamount of image details will be lost in the first and second areas,resulting in different amount of anonymization. By, after downscaling,upscaling the first and second areas to their original number of pixels,the first and second areas will have their original size in theedge-filtered image frame. FIG. 10 schematically illustrates an exampleof an edge-filtered image frame 1000 of a second edge-filtered versionof the captured video stream. In this example, the first resolution of afirst area 1002 of the edge-filtered image frame 1000 is half the imageresolution of the edge-filtered image frame 700 and the secondresolution of a second area 1004 of the edge-filtered image frame 1000is a fourth of the image resolution of the edge-filtered image frame700.

In a fifth alternative way, the providing of the second version of thevideo stream comprises producing the second version of the video streamas a second, edge-filtered, version of the video stream by representingedge points having an edge strength below an edge strength threshold inthe first, edge-filtered, version of the video stream as non-edge pointsin the second, edge-filtered, version of the video stream. FIG. 12schematically illustrates an example of an edge-filtered image frame1200 of a second, edge-filtered, version of a captured video stream,wherein edge points having an edge strength below the edge strengththreshold is suppressed by representing them as non-edge points in thesecond, edge-filtered, version of the video stream. Thereby, the privacyof the one or more objects 104 is increased. It should be understoodthat by increasing the edge strength threshold further, a furtheranonymization of the one or more objects 104 will be obtained and thusalso an even more secure privacy of the one or more objects 104 will beobtained.

In an optional step S316 and when the estimated size in the video streamof the at least one part is below the first threshold, the capturedvideo stream is provided. The captured video stream may be provided bytransmitting the captured video stream to a receiver. As previously,mentioned the receiver may be any device operatively connected, via wireor wirelessly, to the camera 108 or being comprised within the camera108. Thus, it should be understood that the captured video stream may betransmitted to the client 114, the server 116 and/or to the data storage214.

Embodiments also relates to the camera 108 for facilitating installationthereof. The camera 108 comprises the image capturing module 206configured to capture a video stream of a scene 102 when the camera 108is installed with a first field of view, which scene 102 comprises oneor more objects 104.

The camera 108 comprises also the size estimating component 402configured to estimate a size in the video stream of at least one partof the one or more objects 104.

Further, the camera 108 comprises the providing component 404 configuredto, as long as the estimated size in the video stream of the at leastone part of the one or more objects 104 is above a first threshold andbelow a second threshold, provide a first, edge-filtered, version of thevideo stream to secure privacy of the one or more objects depicted inthe video stream.

The providing component 404 is configured to detect and enhance edgepoints and to suppress non-edge points in the captured video stream, andto provide an edge-filtered version of the captured video stream, e.g.,the first and second, edge-filtered, version of the captured videostream as described above. The providing component 404 may be or maycomprise an edge detector configured to provide the edge-filteredversions of the captured video stream.

Furthermore, the providing component 404 is configured to, when thecamera 108 is in the enhanced secure privacy mode of operation, disableprovision of the first, edge-filtered, version of the video stream.

In some embodiments, the providing component 404 is configured toprovide a second version of the captured video stream, which secondversion may be a privacy masked version or a second, edge-filtered,version of the captured video stream.

The providing component 404 may also be configured to provide thecaptured video stream when the estimated of the size in the video streamof the at least one part of the one or more objects 104 is below thefirst threshold.

The camera 108 is configured to, in response to the estimated size inthe video stream of the at least one part of the one or more objects 104being above the second threshold indicating that privacy of at least oneobject is at risk of being revealed, enter the enhanced secure privacymode of operation.

Further, the camera 108 comprises the alert generating component 406configured to, when the camera 108 is in the enhanced secure privacymode of operation, generate an alert to prompt an installer tore-install the camera with a second field of view different from thefirst field of view.

Embodiments also relates to a non-transitory computer-readable mediumhaving stored thereon computer code instructions adapted to carry outembodiments of the method described herein when executed by a devicehaving processing capability.

As described above, the camera 108 may be configured to implement amethod for facilitating installation thereof. For this purpose, thecamera 108 may include circuitry which is configured to implement thevarious method steps described herein.

In a hardware implementation, the circuitry may be dedicated andspecifically designed to implement one or more of the method steps. Thecircuitry may be in the form of one or more integrated circuits, such asone or more application specific integrated circuits or one or morefield-programmable gate arrays. By way of example, the camera 108 mayhence comprise circuitry which, when in use, estimates the size in thevideo stream of at least one part of the one or more objects, and which,when in use and as long as the estimated size in the video stream of theat least one part of the one or more objects is above a first thresholdand below a second threshold, provides a first, edge-filtered, versionof the video stream to secure privacy of the one or more objectsdepicted in the video stream. The camera 108 may further comprisecircuitry which, when in use and in response to the estimated size inthe video stream of the at least one part of the one or more objectsbeing above the second threshold indicating that privacy of at least oneobject is at risk of being revealed, enters an enhanced secure privacymode of operation. Furthermore, the camera 108 may comprise circuitrywhich, when in use and when in the enhanced secure privacy mode,generates an alert to prompt an installer to re-install the camera witha second field of view different from the first field of view, anddisables provision of the first, edge-filtered, version of the videostream.

In a software implementation, the circuitry may instead be in the formof a processor, such as a microprocessor, which in association withcomputer code instructions stored on a (non-transitory)computer-readable medium, such as a non-volatile memory, causes thecamera 108 to carry out any method disclosed herein. Examples ofnon-volatile memory include read-only memory, flash memory,ferroelectric RAM, magnetic computer storage devices, optical discs, andthe like. In a software case, each of the method steps described abovemay thus correspond to a portion of computer code instructions stored onthe computer-readable medium, that, when executed by the processor,causes the camera 108 to carry out any method disclosed herein.

It is to be understood that it is also possible to have a combination ofa hardware and a software implementation, meaning that some method stepsare implemented in hardware and others in software.

It will be appreciated that a person skilled in the art can modify theabove-described embodiments in many ways and still use the advantages asshown in the embodiments above. For example, the camera 108 does notneed to be a single unit comprising the image capturing module 206 andthe image processing and encoding module 214 at one location but itcould be a virtual unit, wherein image capturing part 206 and the imageprocessing and encoding module 214 operate together but they areprovided at different locations. Further, the size estimating component402, the providing component 404 and the alert generating component 406do not need to be arranged in the image processing pipeline 208, butcould be arranged as separate units of the image processing and encodingmodule 214 and could be arranged in communication with the imageprocessing pipeline 208, the encoder 210, the input and output interface212, and the data storage 214. Thus, the concepts should not be limitedto the shown embodiments but should only be defined by the appendedclaims. Additionally, as the skilled person understands, the shownembodiments may be combined.

1. A method in a camera for facilitating installation thereof, themethod comprising: capturing a video stream of a scene when the camerais installed with a first field of view, which scene comprises one ormore objects, estimating a size in the video stream of at least one partof the one or more objects, as long as the estimated size in the videostream of the at least one part of the one or more objects is above afirst threshold and below a second threshold, providing a first,edge-filtered, version of the video stream to secure privacy of the oneor more objects depicted in the video stream; and in response to theestimated size in the video stream of the at least one part of the oneor more objects being above the second threshold indicating that privacyof at least one object is at risk of being revealed, entering anenhanced secure privacy mode of operation comprising: generating analert to prompt an installer to re-install the camera with a secondfield of view different from the first field of view, and disablingprovision of the first, edge-filtered, version of the video stream. 2.The method of claim 1, wherein the enhanced secure privacy mode ofoperation further comprises: providing a second version of the videostream in which the privacy of the one or more objects is furthersecured.
 3. The method of claim 2, wherein providing the second versionof the video stream comprises: producing the second version of the videostream by applying a privacy mask to at least a part of the video streamto secure privacy of the one or more objects depicted in the videostream.
 4. The method of claim 1, wherein providing the first,edge-filtered, version of the video stream comprises: producing thefirst, edge-filtered, version of the video stream by applying an edgefilter to the video stream to enhance edge points in the video streamand to suppress non-edge points in the video stream, wherein pixelvalues of the video stream are represented using a first number ofquantization levels.
 5. The method of claim 4, wherein providing thesecond version of the video stream comprises: producing the secondversion of the video stream as a second, edge-filtered, version of thevideo stream by: before applying the edge filter to the video stream,reducing the spatial resolution of the video stream to reduce the sizein the video stream of the at least one part of the one or more objectsto be below the second threshold.
 6. The method of claim 4, whereinproviding the second version of the video stream comprises: producingthe second version of the video stream as a second, edge-filtered,version of the video stream by: before applying the edge filter to thevideo stream, reducing the number of quantization levels used torepresent pixel values of the video stream from the first number ofquantization levels to a second number of quantization levels.
 7. Themethod of claim 1, wherein providing the second version of the videostream comprises: producing the second version of the video stream as asecond, edge-filtered, version of the video stream by: reducing thespatial resolution of the first, edge-filtered, version of the videostream to obtain the second, edge-filtered, version of the video streamwherein the size of the at least one part of the one or more objects isbelow the second threshold.
 8. The method of claim 1, wherein providingthe second version of the video stream comprises: producing the secondversion of the video stream as a second, edge-filtered, version of thevideo stream by: representing edge points having an edge strength belowan edge strength threshold in the first, edge-filtered, version of thevideo stream as non-edge points in the second, edge-filtered, version ofthe video stream.
 9. The method of claim 1, wherein providing the first,edge-filtered, version of the video stream comprises: transmitting thefirst, edge-filtered, version of the video stream to a receiver; andwherein disabling provision of the first, edge-filtered, version of thevideo stream comprises: disabling transmission of the first,edge-filtered version of the video stream to the receiver.
 10. Themethod of claim 1, wherein disabling provision of the first,edge-filtered, version of the video stream comprises: disabling thecamera from capturing the video stream.
 11. The method of claim 1,wherein disabling provision of the first, edge-filtered, version of thevideo stream comprises: disabling an image sensor of the camera toconvey image frames used to make the captured video stream.
 12. Themethod of claim 1, further comprising: when the estimated size in thevideo stream of the at least one part of the one or more objects isbelow the first threshold, providing the captured video stream.
 13. Acamera for facilitating installation thereof, the camera comprises: animage capturing module configured to capture a video stream of a scenewhen the camera is installed with a first field of view, which scenecomprises one or more objects, a size estimating component configured toestimate a size in the video stream of at least one part of the one ormore objects, a providing component configured to, as long as theestimated size in the video stream of the at least one part of the oneor more objects is above a first threshold and below a second threshold,provide a first, edge-filtered, version of the video stream to secureprivacy of the one or more objects depicted in the video stream; and inresponse to the estimated size in the video stream of the at least onepart of the one or more objects being above the second thresholdindicating that privacy of at least one object is at risk of beingrevealed, the camera is configured to enter an enhanced secure privacymode of operation wherein: an alert generating component is configuredto generate an alert to prompt an installer to re-install the camerawith a second field of view different from the first field of view, andwherein the providing component is configured to disable provision ofthe first, edge-filtered, version of the video stream.
 14. Anon-transitory computer-readable medium having stored thereon computercode instructions adapted to carry out a method, when executed by adevice having processing capability, the method comprising: capturing avideo stream of a scene when the camera is installed with a first fieldof view, which scene comprises one or more objects, estimating a size inthe video stream of at least one part of the one or more objects, aslong as the estimated size in the video stream of the at least one partof the one or more objects is above a first threshold and below a secondthreshold, providing a first, edge-filtered, version of the video streamto secure privacy of the one or more objects depicted in the videostream; and in response to the estimated size in the video stream of theat least one part of the one or more objects being above the secondthreshold indicating that privacy of at least one object is at risk ofbeing revealed, entering an enhanced secure privacy mode of operationcomprising: generating an alert to prompt an installer to re-install thecamera with a second field of view different from the first field ofview, and disabling provision of the first, edge-filtered, version ofthe video stream.